Author: andrew Date: Mon Aug 27 11:14:49 2018 New Revision: 338337 URL: https://svnweb.freebsd.org/changeset/base/338337
Log: Ensure we have a large enough stack for the lua loader Lua has a few places where it allocates a large buffer on the stack. This is normally fine, except there are a few places where there can be multiple frames with this buffer. This can cause a stack overflow on some arm64 SoCs. Fix this by allocating our own stack in loader.efi large enough for these objects. The required size has been found by tracing how the stack pointer changes in a virtual machine and found to be no larger than 50kB. A larger stack is allocated to reduce the likelihood of overflow from future changes. Reviewed by: kevans Approved by: re (kib) Differential Revision: https://reviews.freebsd.org/D16886 Modified: head/stand/efi/boot1/Makefile head/stand/efi/loader/arch/arm64/start.S Modified: head/stand/efi/boot1/Makefile ============================================================================== --- head/stand/efi/boot1/Makefile Mon Aug 27 10:08:27 2018 (r338336) +++ head/stand/efi/boot1/Makefile Mon Aug 27 11:14:49 2018 (r338337) @@ -6,6 +6,7 @@ PROG= boot1.sym INTERNALPROG= WARNS?= 6 +CFLAGS+= -DEFI_BOOT1 # We implement a slightly non-standard %S in that it always takes a # CHAR16 that's common in UEFI-land instead of a wchar_t. This only # seems to matter on arm64 where wchar_t defaults to an int instead Modified: head/stand/efi/loader/arch/arm64/start.S ============================================================================== --- head/stand/efi/loader/arch/arm64/start.S Mon Aug 27 10:08:27 2018 (r338336) +++ head/stand/efi/loader/arch/arm64/start.S Mon Aug 27 11:14:49 2018 (r338337) @@ -160,6 +160,23 @@ _start: ldp x0, x1, [sp], #16 +#ifndef EFI_BOOT1 + /* + * Load the stack to use. The default stack may be too small for + * the lua loader. + */ + adr x2, initstack_end + mov sp, x2 +#endif + bl efi_main 1: b 1b + +#ifndef EFI_BOOT1 +.bss + .align 4 +initstack: + .space (64 * 1024) +initstack_end: +#endif _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
